Apparatus for drawing bags,envelopes and the like



- June 10, 1969 K. STEMMLER APPARATUS FOR DRJXWING BAGS, ENVELOPES AND THE LIKE Filed Feb. 24',=19e7' 10 if 13 Fig.1

Inventor KStemm/er ATTO (LNES:SS-

United States Patent 3,448,977 APPARATUS FOR DRAWING BAGS, ENVELOPES AND THE LIKE Kurt Stemmler, Irlich (Rhine), Germany, assignor to Winkler & Dunnebier KG, Neuwied (Rhine), Germany,

a corporation of Germany Filed Feb. 24, 1967, Ser. No. 618,441 Claims priority, application Germany, Mar. 17, 1966,

W 41,161 Int. Cl. B65h 3/08, /08 U.S. Cl. 271-5 6 Claims ABSTRACT OF THE DISCLOSURE Flat stiff bags, envelopes and similar articles arranged in a vertical stack are fed singly to a machine which applies adhesive to them by a feeding apparatus which includes a suction device separating an article from the stack and other suction devices moving the separated article to conveyor discs with the aid of presser rollers.

This invention relates to an apparatus for feeding stiff, folded fiat bags, envelopes and similar articles made from paper or the like singly one by one into a machine for their processing, for example, for the application of adhesive to the open closure flaps thereof and perhaps also, where latex is used, to the corresponding points of contact on the back of the articles while maintaining an equal distance between the articles after the drawing-in operation. Prior thereto the articles are stacked edgewise on a preferably somewhat inclined supporting surface.

German Patent No. 566,786 describes an apparatus for extracting the bottom sheet from a steeply inclined stack of sheets wherein each sheet which is to be drawn in is fed by a pivoting suction arm and wiper segments to take-off rollers with the aid of a stream of compressed air projected from above to loosen the end of the stack, the sheet being placed against a rotatable horizontal roller supporting the stack approximately in the middle thereof. The sheets are cut blanks of thin paper intended to be folded as envelopes. They are gripped at their upper end and are removed upwardly from the stack between the wiper segments and a presser roller.

This prior art apparatus is unsuitable for several reasons for the purposes of the present invention, namely, for the feeding of folded flat bags, envelopes or the like to a machine applying adhesive to their open closure flaps. To avoid damage, these articles should not be bent to the extent which takes place in the known apparatus. Furthermore, they should be drawn in with their edge opposite the open sealing flap at the front, in the direction of travel, in other words, they should be drawn off the stack by the suction arm at the straight edge on which they stand in the stack. The known apparatus is unsuitable for this operation.

An object of the present invention is the provision of a feeding apparatus for bags, envelopes and other articles which will not have the drawbacks of prior art devices.

Other objects will become apparent in the course of the following specification.

The objects of the present invention may be achieved by an apparatus in which the articles stand edgewise in the form of a stack on a preferably slightly inclined supporting surface, the article which is to be drawn in at a given time being bent away from the stack by a suction device which may or may not be pivotable, and being passed to a rotating conveyor element which, in conjunction with presser rollers, removes the article from the stack, the rotating conveyor element consisting of one or more discs, the diameter of which is at least approximately three times the length of the smallest size of 3,448,977 Patented June 10, 1969 article which is to be drawn in, and the center of which is situated approximately one-third of its diameter above the plane of the plate which carries the stack of articles. In order to bend away the article which is to be isolated, the suction device may be constructed as a tilting device pivotable approximately transversely to the plate carrying the stack and engaging, the bottom edge of the article. The apparatus also includes a tongue adapted to pivot between the article bent away by the suction device and the remainder of the stack, with which alternately insertable tongues are associated. Furthermore, the apparatus is provided with pivotable suction devices which extend approximately parallel to the plate carrying the stack, and which take over the isolated article from the first-mentioned suction device and move it to the conveyor discs. Finally the apparatus may include means for pushing the presser rollers cooperating with the conveyor discs along the periphery of the conveyor discs, over the article which is drawn upon these discs.

The unusually large diameter of the conveyor discs provides for a slight fiection in the articles and prevents their being damaged. The location of the center of the conveyor discs above the plate carrying the stack provides the necessary space for the first-mentioned suction device which is to bend the article to be isolated away from the stack and for the suction devices which are to accept the article from the tilting suction device and pass it to the conveyor discs. The arrangement of the last-mentioned suction devices permits an upward movement of the tilting suction device so that it can start applying suction to the next article which is to be isolated, long before the preceding article has been moved out of the way of the next article by the conveyor discs. Thus a considerably longer time is available to the tilting suction device during which it can attract and bend away the article to be isolated from the stack than if it also has to move the article to the conveyor discs. This provides a more reliable separation of the stiff articles.

The synchronized displacement of the presser rollers cooperating with the conveyor discs along the periphery of the conveyor discs over the article which is drawn onto the latter, provides a non-slip entraining of the article by the discs under very slight differences in spacing of articles drawn into the machine.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings showing by way of example, a preferred embodiment of the inventive idea.

In the drawings:

FIGURE 1 is a plan view of the apparatus;

FIGURE 2 is a longitudinal cross section through the apparatus along the line IIII in FIG. 1; and

FIGURE 3 is a detail partly sectional view showing the tilting suction ,device in its inoperative position.

The drawings show a machine having side walls 1 and 2 in which shafts 3, 4 and 5 are rotatably mounted. Keyed 0n the shaft 3 are two cylindrical discs 6, two cams 7 and a sprocket 8. Keyed on shaft 4 are sprockets 9, 10 and 11 and a cam 12. Keyed on shaft 5 are a sprocket 13 and cams 14, 15 and 16. The shafts 3, 4 and 5 are driven by the sprocket 11 which is rigidly mounted on the shaft 4 and the roller chains 17 and 18' in the direction indicated by the arrows, whereby the shaft 3 carries out one-half of a revolution while shafts 4 and 5 each carry out one revolution for every operating stroke of the machine. The sprocket 11 is operated by the main drive of the machine (not shown).

A plate 19 is attached to the side walls 1, 2 of the machine, in a manner not illustrated. The plate 19 is preferably slightly inclined. Rotatably mounted under the plate 19, in bearings 20 and 21, is a shaft 22 having rollers 23 and two shafts 24 having rollers 25. Stretched over the rollers 23, are belts 26. Some of the rollers project through openings formed in the plate 19 so that the upper strand of the belts rests on the top of the plate 19. Through a sprocket 24 connected to the machine drive, the machine causes one of the shafts 25 to rotate slowly at a regulable speed in the direction of the arrow, so that a stack 27 of envelopes or other articles standing edgewise on the plate 19' and on the belts 26 located above the said plate, is fed forwardly in the direction of the arrow. The foremost article in the stack which is to be extracted rests at the top against rodshaped stops 28 which are rigidly mounted on a crossmember 29 which is held by supports 30 bolted to the side walls 1 and 2 of the machine. At its bottom edge, the foremost article is held by tongues 31 and a tongue 32 which are moved in a manner to be described hereinafter.

The tongues 31 and 32 have identically shaped tips which alternately engage over the bottom edge of the foremost article or release the article. The tongues 31 are mounted rigidly on a shaft 33 which is pivotally mounted in the side walls and which carries out an angular swinging movement by means of a level 34 fixed upon the shaft 33 and carrying a roller 35 engaging the cam 16 on the shaft 5. A spring, not shown, holds the roller 35 in permanent contact with the cam 16. The tongue 32 is secured by means of a holder 36 to a shaft 37 rotatably mounted in the side walls of the machine. Through an arm 38 which is fixed upon the shaft 37 and a roller 39 which is rotatably mounted on the arm and which engages the cam 15, the shaft 37 is caused to carry out a certain angular movement by the cam 15 upon the shaft 5. A spring 40 draws the roller 39 permanently against the cam 15.

In the embodiment illustrated in FIG. 3 the tongue 32 has a projection 32 which controls the tilting movement of the tilting suction device 41 in a manner which is to be described hereinafter. The suction device which serves to separate the foremost article from those behind it (FIGS. 2 and 3) consists mainly of the upper part 41 with a suction aperture 42, which is mounted on a base 44 and pivots about a pin 43. Between an arm 45 of the upper part 41 and the base 44 there is a spring 46 which swings the upper part 41 until a stop 47 bears on the base. The base 44 is firmly mounted on a tube 48 which is held firmly in a holder 49. The holder 49 is keyed on a shaft 50 which is rotatably mounted in the side walls of the machine. The suction aperture 42 is air-conductively connected with the tube 48, the hollow holder 49' and with a longitudinal bore 51 provided in the shaft 50. The shaft 50 together with the suction device 41 is caused to carry out an angular rotary movement by an arm 52 mounted rigidly on the shaft 50 and carrying a roller 53 which is pressed against the cam 14 by a spring 54.

It should be noted, however, that if the articles being processed, such as envelopes, are not too stiff, the suction device 41 may be replaced by one which does not have a tilting motion. In that case the part 41 may have the shape of a rigid mouthpiece firmly connected to the tube 48. Then the pin 43, the arm 45, the spring 46 and the cam 32' may be eliminated altogether.

The illustrated machine has two additional suction devices which serve to move the foremost article to the discs 6. Each of these devices has a suction nozzle 55 with a vacuum tube 55 and a holder 56 which is mounted rigidly on an arm 58 adapted to pivot about a pin 57 which is fixed in a side wall of the machine. A roller 59 is pivotally mounted on the arm 58 and is pressed by a spring 60 against the cam 7, thus controlling the reciprocating movement of the suction device 55. Control valves which are not illustrated are used to connect the suction devices 41 and 55 with a vacuum pump (not shown) and to interrupt this connection according to the operational cycle of the machine.

The space between the stack 27 and the discs 6, in

addition to containing the described tongues and suction devices, also includes pressure rollers 61 which are pivotally mounted on arms 62 and are pressed by springs 63 against the periphery of the discs 6. Each of the two arms 62 is pivotally connected to an arm 64 rigidly mounted on a shaft 63 which is rotatably mounted in the side walls. An arm 65 which is also rigid on the shaft 63 carries a roller 66 which is pressed by a spring 67 against the cam 12. The cam 12 is so shaped that, in their lowest position, the rollers 61 are out of the 'way of an article which is drawn to the discs 6 by the suction devices 55 while, in their highest position, the article is pressed firmly against the rotating discs 6 so that it is entrained thereby.

Under the discs 6 is a guide plate 68 provided with the necessary apertures for the tongues, suction devices and rollers bearing on the discs. The plate 68 is an extension of the plate 19 and is secured to the side walls 1, 2 in a manner not shown. The plate 68 is at a distance from the discs 6 which allows passage for the article. Rollers 69 which are spring-mounted in a manner not shown press the article which is moving over and along the guide plate 63 against the discs 6.

Beyond the guide plate 68 is a plurality of shafts 70 which are rotatably mounted in the side walls and are engaged by rollers 71 which are spring-loaded, in a manner not shown, so that they are pressed against the shafts 70 and transport the article further over the guide plates 72. The shafts 70 are driven in the direction indicated by the arrow, at the peripheral speed of the discs 6 by means of gear wheels 73 and intermediate wheels, not shown.

The operation of the described apparatus is as follows: While the tongue 32 is in its lowest position, namely, while theforemost article in the stack rests only on the fixed stops 2!; and the pivotable tongues 31, the suction device 41, 44 moves into the position shown in FIG. 3, attracts the foremost article by suction and remains in this position. In the meantime, the tongue 32. moves upwardly. The projection 32' of the tongue 32 slides along the bent arm 45 and pivots the top part 41, together with the bottom edge of the foremost article, which has been sucked against the top part 41, into the position shown in FIG. 2, whereby the tip of the tongue 32 penetrates into the gap which has been thus produced between the foremost article and its neighbor. At the same time, the suction devices 55 move out of their position shown in FIG. 2, to the foremost article and attract it by suction. The suction device 41 is cut off from the vacuum pump and, together with the tongues 31, moves downwardly out of the path of the foremost article. Thereupon the suction devices 55 with the foremost article, which they are gripping, swing back into the position shown in FIG. 2. The tongues 31 and the suction device 41 begin their upward movement while the tongue 32 starts to move downwardly. As soon as the rollers 61, in the course of their upward movement, reach the article which is held by the suction devices 55 and press it against the periphery of the discs 6, the vacuum in the suction devices 55 is cut off and the article is entrained by the discs 6. Then the cycle can re-commence.

Apart from the fact that the article which is to be fed into the machine is, in a manner known per se, virtually relieved of the weight of all other articles in the stack due to the fact that the stack is standing on edge, the particular advantage of the apparatus according to the present invention, as compared with known machines, resides in the fact that, by virtue of the additional suction devices 55 and the diameter of the discs 6, which is relatively great as compared to the height of the articles, the tilting suction device 41, 44 is already being moved towards the next article and can attract it, before the article previously separated from the stack has been away from the stack by the discs 6. Therefore, a far greater proportion of the time gap between two subsequent articles is available for the reliable separation of one article from the stack, than was available with the known machines. As a matter of fact, as already stated, the diameter of each of the discs 6 should preferably be equal to approximately three times the height of the smallest size of the article which is to be fed into the machine, while its center should be located above the plane of the plate 19 carrying the stack to the extent of approximately one-third of the diameter of the disc.

It is apparent that the example described above has been given solely by way of illustration and not by way of limitation and that it is capable of many variations and modifications within the scope of the present invention. All variations and modifications are to be included within the scope of the present invention.

What is claimed is:

1. An apparatus for feeding bags, envelopes and similar articles singly from a stack to a machine, said apparatus comprising a support adapted to carry a stack of articles located edgewise thereon, a suction device for bending the outermost article in said stack away from the stack, at least one rotary conveyor disc, said conveyor disc having a diameter equal to at least substantially three times the height of said stack, the center of said disc being located above said support to the extent of substantially one-third of the diameter of the disc, pivoted suction devices removing said outermost article from the first-mentioned suction device and moving it to said conveyor disc, and movable presser rollers for pressing said outermost article against said conveyor disc.

2. An apparatus for feeding bags, envelopes and similar articles singly from a stack to a machine, said apparatus comprising a support adapted to carry a stack of articles located edgewise thereon, a suction device for bending the outermost article in said stack away from the stack, at least one rotary conveyor disc, pivoted suction devices removing said outermost article from the first-mentioned suction device and moving it to said conveyor disc, presser rollers and means moving said presser rollers toward said conveyor disc to press said outermost article against said disc and then removing said pressing rollers from the path of movement of the following article.

3. An apparatus for feeding bags, envelopes and similar articles singly from a stack to a machine, said apparatus comprising a support adapted to carry a stack of articles located edgewise thereon, a suction device for bending the outermost article in said stack away from the stack, means supporting said suction device for a tiltable movement transversely to said support, said suction device having a mouthpiece adapted to engage a lower edge of said outermost article and withdraw it from said stack, a tongue movable into the space between said stack and said lower edge of the outermost article after the lower edge has been withdrawn, and other movable tongues alternately supporting said lower edge and withdrawing thereform, at least one rotary conveyor disc, pivoted suction devices removing said outermost article from the first-mentioned suction device and moving it to said conveyor disc, and movable presser rollers for pressing said outermost article against said conveyor disc.

4. An apparatus in accordance with claim 3, wherein the first-mentioned suction device has a tiltable upper part adapted to rest against the outermost article and tilted along with the lower edge thereof when the lower edge is withdrawn.

5. An apparatus in accordance with claim 4, wherein the first-mentioned tongue engages and actuates said tiltable upper part.

6. An apparatus in accordance with claim 4, comprising means pivotally supporting said suction devices and said tongues and cam-actuated means actuating said suction devices and said tongues.

References Cited UNITED STATES PATENTS 2,060,800 11/1936 Ehrig 27128 FOREIGN PATENTS 926,340 4/ 1955 Germany. 649,530 1/1951 Great Britain. 1,235,339 5/1960 France.

RICHARD E. AEGERTER, Primary Examiner.

US. Cl. X.R. 271-26 

